GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 626239  Size: SH
  1. In order to gain access to the throttle body mounting bolts, remove the intake manifold. Refer to the intake manifold removal procedure in Engine Mechanical.

  2. Object Number: 626164  Size: SH
  3. Remove the MAF/IAT throttle body extension.
  4. Remove the throttle body (1) mounting bolts.
  5. Remove the throttle body (1) and the gasket (2) from the throttle body spacer (3).

Disassemble Procedure

    Notice: Do not immerse the TP sensor and IAC valve in any type of cleaner. This cleaning method may damage these electronic components.

    Notice: Use care when cleaning the old gasket from the aluminum surfaces in order to prevent damage to the sealing surfaces.


    Object Number: 18398  Size: SH
  1. Remove the throttle position (TP) sensor bolts (3) from the TP sensor (2). Refer to Throttle Position Sensor Replacement .
  2. Remove the TP sensor (2) from the throttle body.
  3. Remove the IAC valve bolts (4) from the IAC valve (1). Refer to Idle Air Control Valve Replacement .
  4. Remove the IAC valve (1) from the throttle body.
  5. Discard the O-rings.
  6. Notice: Do not use a cleaner which contains methyl ethyl ketone. This extremely strong solvent may damage components and is not necessary for this type of cleaning.

    Use a carburetor cleaner in order to remove deposits.

    Refer to the instructions provided with the cleaner.

  7. Clean the throttle body gasket surfaces.

Assemble Procedure


    Object Number: 18398  Size: SH
  1. Install the new O-rings to the sensors.
  2. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the IAC valve to the throttle body.
  4. Tighten
    Tighten the bolts to 3 N·m (27 lb in).

  5. Install the TP sensor to the throttle body.
  6. Tighten
    Tighten the TP bolts to 2.3 N·m (20 lb in).

Installation Procedure

Important: The outlet of the air cleaner assembly and the MAF/IAT sensor inlet duct must line up when completely installed. Misalignment may cause incorrect airflow readings resulting in malfunction indicator lamp (MIL) illumination or a driveability concern. An improperly installed inlet duct assembly or air cleaner assembly may cause misalignment.

Important: DO NOT reuse the old throttle body gasket.


    Object Number: 626164  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install bolts from the throttle body (1) to throttle body spacer (3) and tighten the bolts.
  2. Tighten
    Tighten all 4 throttle body attaching bolts to 12 N·m (106 lb in).


    Object Number: 626164  Size: SH
  3. Reinstall the intake manifold. Refer to the intake manifold installation procedure in Engine Mechanical.
  4. Reinstall the engine dress cover.